CVE-2025-59535DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. Prior to version 10.1.0, arbitrary themes can be loaded through query parameters. If an installed theme had a vulnerability, even if it was not used on any page, this could be loaded on unsuspecting clients without knowledge of the site owner. This issue has been patched in version 10.1.0.